Process method for co-producing mesitylene and isophorone through directional polycondensation of acetone

Abstract

The invention relates to a process method for co-producing mesitylene and isophorone by directional polycondensation of acetone, which comprises the following steps: by taking acetone as a raw material, continuously carrying out polycondensation on the acetone, an acid catalyst and a basic catalyst under certain temperature and pressure conditions to synthesize mesitylene and isophorone products, the process can be used for industrial large-scale production of mesitylene and isophorone products from acetone, compared with the existing technology for preparing mesitylene and isophorone, the preparation method of the catalyst is simple and convenient, the price is low, the activity and selectivity are high, the stability is good, the conversion rate of acetone is greatly improved, and the catalyst adopted by the technology is suitable for industrial production.

Description

Technical Field

[0001] The invention relates to the field of organic synthesis chemical industry, and more specifically to a process for co-producing mesitylene and isophorone by directional polycondensation of acetone. Background Art

[0002] Isophorone has a high boiling point and low hygroscopicity. It has good solubility, dispersibility and leveling properties. It is a good solvent for polymer materials and can dissolve nitrocellulose, acrylates, alkyd resins, polyesters and epoxy resins. It is an intermediate for various important products such as alcohols, acids, amines, esters and isocyanates, and has a wide range of uses in industries such as plastics, pesticides, medicines, and coatings.

[0003] At present, the preparation methods of isophorone mainly include the mesityl oxide method and the acetone condensation method. Among them, the mesityl oxide method has the characteristics of mild reaction conditions, simple process, and convenient operation, but its raw material price is relatively expensive and difficult to promote and apply. The acetone gas-solid multiphase condensation method has low raw material cost and broad industrialization prospects, and is the most advantageous synthesis method.

[0004] Mesitylene (MS) is very active in chemical properties and is easily halogenated, nitrated and sulfonated. Mesitylene is an important chemical raw material that can be used to prepare a variety of fine chemical products such as dye intermediate mesitylene amine, antioxidant Lonox330, and anti-ultraviolet oxidation stabilizer mesitylene phenol. It is also an important raw material for the production of alkyd resins and high-temperature plasticizers.

[0005] The synthesis method of mesitylene is relatively mature. The traditional synthesis methods mainly include: extractive distillation method, heavy aromatic hydrocarbon distillation separation method, gas phase isomerization reaction of mesitylene, atmospheric pressure liquid phase isomerization reaction of mesitylene, atmospheric pressure liquid phase alkylation of mesitylene to produce mesitylene and co-production of mesitylene, and combined isomerization and alkylation of mesitylene to produce high-purity mesitylene and co-production of mesitylene, etc.

[0006] The extractive distillation method uses dimethyl phthalate (DMT) as a solvent and extractive distillation to separate C9 aromatics as an example. The main process is carried out through four extractive distillation towers. From the top of tower 1 and tower 2, mesitylene and m- and p-methylethylbenzene can be obtained respectively; from the bottom of tower 3, a high boiling point solvent is recovered; from the top of tower 4, o-methylethylbenzene is obtained, and from the bottom of tower 4, unsimilar trimethylbenzene and other heavy components are obtained. This process can obtain 87% mesitylene, but the product purity is relatively low. In addition, this method requires more equipment and has high operating costs. The early domestic patent CN1513818 reported a separation process of C9 aromatics by alternating distillation and extraction. The C9 aromatics were separated by the bottom liquid of a multi-stage extraction circulating tower to achieve the purpose of purification. This method requires more extraction and separation equipment and has high operating costs. Currently, the domestic patent CN115872828B reports a method for separating and purifying mesitylene from reformed C9 aromatics using a eutectic solvent. The components in the eutectic solvent of this method are cheap and easy to obtain, which greatly reduces the solvent cost.

[0007] The patent US258961A of Standard Oil Company of the United States reported a method for isomerizing a trimethylbenzene mixture and selectively extracting meta-trimethylbenzene, and the product produced by high-temperature treatment of trimethylbenzene with liquid HF and BF3 was treated and separated. This method requires hydrogen conditions and high temperature and high pressure, and the reaction equipment is relatively complex, and the requirements for reaction conditions are also relatively harsh, so the production cost is relatively high. The domestic CN115770611B patent reported a preparation method and application of a catalyst for isomerizing meta-trimethylbenzene with an organic ammonium salt or ammonium bicarbonate modified MCM-22 catalyst for preparing mesitylene, and the catalyst has high isomerization activity and high mesitylene yield.

[0008] Domestic patent CN113045379A reports a method for co-producing mesitylene and tetramethylbenzene by alkylation-isomerization of C8 or C9 aromatics, which is a method for alkylating C8 or C9 aromatics and methanol to produce mesitylene. The process can achieve high product purity and high mesitylene selectivity, but the operating cost of the multi-stage distillation separation device is high.

[0009] The process route of preparing mesitylene from acetone by heterogeneous catalysis has the advantages of environmental protection, high conversion rate, and easy scale-up. However, due to the complexity of the acetone condensation process, it has a large number of by-products and low selectivity for mesitylene. At present, catalysts for condensation trimer of acetone are mainly divided into two categories. One category is mainly based on solid alkaline magnesium-aluminum composite oxides, which are used to catalyze the condensation of acetone to produce dimer isoacetone alcohol or further trimerized phorone and isophorone. Patents have been reported both at home and abroad. US5153156 patent reports a catalyst obtained by spraying synthetic clay on the surface of MgO-Al2O3 by spraying. The selectivity of catalyzing condensation of acetone to mesityl oxide and isophorone is low at 27.3%. CN101462043A patent reports that a solid alkali-modified magnesium-aluminum composite oxide is obtained by mixing, crystallizing and calcining salt solutions of magnesium-aluminum modified metals in an alkaline environment. The catalyst is used for the reaction of condensation of acetone to produce isophorone. The conversion rate under normal pressure is as high as 38.2%, the selectivity of isophorone is 77.8%, and the total selectivity of isophorone and mesityl oxide reaches 87.8%. In the patent CN109926040A, a template is used to prepare a composite oxide of a modified metal and magnesium aluminum by precipitation method. In the reaction of preparing isophorone by condensation of acetone, the reaction temperature is 250°C to 300°C, the acetone mass space velocity is 1 to 8 h under normal pressure. -1 , the acetone conversion rate is as high as 45%, the isophorone selectivity is 75%, and the isophorone and isophorone selectivity is 90%. This technology is suitable for the industrial production of isophorone; another type of solid acid mainly composed of modified aluminosilicate zeolite loaded with metal oxides can be used to catalyze the condensation of acetone with mesitylene and benzene ring-containing compounds. There are many foreign patent reports. US2917561A patent reports a metal tantalum in the range of about 0.05 to 5% by weight as an active component loaded, and the carrier is selected from aluminosilicate or a zeolite with a porous structure as a catalyst for a heterogeneous acetone condensation process. US5087781A patent reports a catalyst formed by Pd loaded on a mixture of MoO3 and AhO3 (0.1-1% of the weight of Pd), achieving an acetone conversion rate of 42.5% and a selectivity for meta-trimethylbenzene of 44.2%. US3201485A patent improves the type of loaded metal, loading Nb catalyst on silica, achieving an acetone conversion rate of 30% and a selectivity for mesitylene of 65%. An earlier domestic patent CN1087280C discloses a production process for preparing high-purity mesitylene from acetone, in which acetone and carrier gas nitrogen are mixed and pumped into a fixed bed reactor for catalytic condensation with a silicon-aluminum catalyst impregnated with metal zirconium. The product in the reactor is then pumped into a cooler for gas-liquid separation to remove nitrogen, and the remaining liquid is pumped into a heater for heating. The gas-liquid mixed phase finally enters a distillation tower for distillation to separate high-purity mesitylene. The catalyst used in this process has a maximum selectivity of 50.1% for mesitylene.

[0010] The production process of mesitylene reported so far is mainly based on the separation of C9 aromatics and the isomerization of partial trimethylol. The main problems faced by this method are that there are many extraction and separation equipment, high operating costs, high temperature and high pressure in some operating conditions, and there are few reports on the method of synthesizing mesitylene by acetone polycondensation, which has the prospect of industrialization. Therefore, in order to effectively improve the selectivity of preparing mesitylene by catalytic condensation of acetone and the conversion rate of acetone per pass, reduce the production cost of traditional mesitylene and improve the conversion rate of acetone polycondensation, the present invention provides a process method for efficiently realizing the co-production of mesitylene and isophorone by directional catalytic condensation of acetone. Summary of the invention

[0011] In order to solve the above technical problems existing in the prior art, the purpose of the present invention is to provide a process for the directional polycondensation of acetone to co-produce mesitylene and isophorone, by using economical and affordable acetone as a raw material, continuously and efficiently achieving the co-production of mesitylene and isophorone.

[0012] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions.

[0013] The invention discloses a process for co-producing mesitylene and isophorone by directional polycondensation of acetone. Acetone is used as a raw material and is continuously polycondensed with an acidic catalyst and a basic catalyst under certain temperature and pressure conditions to synthesize mesitylene and isophorone products.

[0014] Preferably, the acidic catalyst and the alkaline catalyst are independently loaded into two reactors.

[0015] Preferably, the acidic catalyst and the alkaline catalyst are mixed in a certain ratio in the same reactor, and the mixed loading ratio of the acidic catalyst to the alkaline catalyst is 0:10 to 10:0.

[0016] Preferably, the acetone condensation reaction conditions are: inert gas environment reaction pressure 0.1-0.5 MPa, reaction temperature 280°C-380°C, liquid hourly space velocity 1-10h -1 .

[0017] Preferably, the acidic catalyst is a catalyst for catalyzing the polycondensation of acetone into mesitylene, including a metal / transition metal supported catalyst.

[0018] Preferably, the oxide carrier in the metal / transition metal supported catalyst is one or more of alumina, amorphous silica-alumina, silicon dioxide, zirconium oxide and titanium oxide;

[0019] The active metal is selected from one or more of vanadium, niobium, tantalum and molybdenum;

[0020] Calculated by weight percentage, the content of the metallic component is 5% to 10% in terms of oxide.

[0021] Preferably, the acidic catalyst is a catalyst for catalyzing the polycondensation of acetone into mesitylene, including a molecular sieve catalyst, and the molecular sieve catalyst is one or more of USY molecular sieve, SAPO molecular sieve, Beta molecular sieve, ZSM-5 molecular sieve and MFI molecular sieve.

[0022] Preferably, the acidic catalyst is Ta2O5 / SiO2.

[0023] Preferably, the alkaline catalyst is a catalyst for catalyzing the polycondensation of acetone to isophorone, including an alkali metal oxide / composite oxide catalyst or an alkali metal hydroxide / composite oxide catalyst;

[0024] Alkali metal oxide / oxide catalyst, the oxide in the alkali metal hydroxide / oxide catalyst is selected from one or more of aluminum oxide, zirconium oxide and titanium oxide;

[0025] The metal in the alkali metal oxide or its hydroxide is one or more of zinc, calcium and magnesium;

[0026] Calculated by weight percentage, the content of alkali metal, calculated as oxide or hydroxide, is 5% to 10%.

[0027] Preferably, the alkaline catalyst is ZnO / Al2O3.

[0028] Compared with the prior art, the production process of catalytic acetone polycondensation to co-produce mesitylene and isophorone proposed in the present invention has the following beneficial effects:

[0029] (1) The present invention proposes a new process for catalyzing acetone to co-produce mesitylene and isophorone, and provides technical guidance for industrial production.

[0030] (2) The complex equipment requirements and separation costs in the traditional mesitylene production method are reduced, the reaction equipment and separation equipment are reduced, the process flow is simple, and the overall selectivity of the value-added products mesitylene and isophorone is improved.

[0031] (3) Compared with single-product catalysis, the acetone conversion rate is greatly improved, the catalyst utilization rate is improved, and the final waste is less.

[0032] (4) The catalyst preparation process is simple, the preparation cost is low, and it can be directly applied to commercial molecular sieve catalysts.

[0033] (5) The prepared catalyst has a short start-up time, strong resistance to carbon deposition, and can operate stably for a long period of time. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a schematic diagram of the process flow proposed in Examples 1-3 of the present invention;

[0035] Figure 2 This is a schematic diagram of the process flow proposed in Examples 4-6 of the present invention.

[0036] In the figure: 1, acetone raw material; 2, first reaction mixed product; 3, unreacted acetone and part of the dimerization product isopropylidene oxide; 4, mesitylene; 5, isophorone; 6, polymer mixture; 7, reactor for co-production of mesitylene and isophorone; 8, separation device; 9, reactor for synthesizing mesitylene; 10, reactor for synthesizing isophorone; 11, second reaction mixed product; 12, third reaction mixed product. DETAILED DESCRIPTION

[0037] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0038] It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments may be combined with each other; and, based on the embodiments in this disclosure, all other embodiments obtained by ordinary technicians in this field without making any creative work are within the scope of protection of this disclosure.

[0039] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein may be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present disclosure, it should be understood by those skilled in the art that an aspect described herein may be implemented independently of any other aspect, and two or more of these aspects may be combined in various ways. For example, any number of aspects described herein may be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein may be used to implement this device and / or practice this method.

[0040] Example 1

[0041] like Figure 1 As shown, a production process for catalytic acetone polycondensation to co-produce mesitylene and isophorone, the process method uses acetone as the starting raw material, the acetone raw material 1 sequentially enters the upper section of the co-production mesitylene and isophorone reactor 7 filled with catalyst Cat1 and the lower section Cat2 to synthesize mesitylene and synthesize isophorone, and finally enters the product separation device 8 to obtain mesitylene and isophorone products with higher purity. The production process of acetone polycondensation to co-produce mesitylene and isophorone is as follows:

[0042] Acetone raw material 1 enters the co-production of mesitylene and isophorone reactor 7. The upper section of Cat1 is filled with active metal-supported catalyst Ta2O5 / SiO2, and the synthesis of mesitylene is carried out under the action of acidic catalyst. The lower section of Cat2 is filled with alkali metal composite oxide catalyst ZnO / Al2O3, and the synthesis of isophorone is carried out under the action of alkaline catalyst. The catalyst loading ratio in Cat1 and Cat2 is 2:1. The reaction temperature is 340℃, the reaction pressure is 0.1MPa, and the space velocity is 2h -1 The first reaction mixture product 2 obtains unreacted acetone and part of the dimer mesityl oxide 3, mesitylene 4, isophorone 5 and part of the polymer mixture 6.

[0043] Finally, the mixed product enters the separation device 8, and according to the difference in boiling points, high-purity mesitylene 4 and isophorone 5 are obtained after separation, the unreacted acetone and part of the dimerization product mesityl oxide 3 are recycled by reflux, and part of the polymer mixture 6 is treated as tail liquid.

[0044] The acetone conversion rate is >63%, the mesitylene selectivity is >50%, the isophorone selectivity is >45%, the purity of the final product mesitylene is >99%, and the purity of isophorone is >99%.

[0045] Example 2

[0046] like Figure 1 As shown, a production process for co-producing mesitylene and isophorone by catalytic condensation of acetone, the process method uses acetone as the starting raw material, and the acetone raw material 1 sequentially enters the upper section filled with catalyst Cat1 and the lower section Cat2 in the co-production reactor 7 for mesitylene and isophorone to synthesize mesitylene and synthesize isophorone, and finally enters the separation device 8 to obtain mesitylene and isophorone products with higher purity. The production process of acetone condensation co-production of mesitylene and isophorone is as follows:

[0047] Acetone raw material 1 enters the co-production of mesitylene and isophorone reactor 7. The upper section of Cat1 is filled with active metal-supported catalyst Ta2O5 / SiO2, and the synthesis of mesitylene is carried out under the action of acidic catalyst. The lower section of Cat2 is filled with alkali metal composite oxide catalyst ZnO / Al2O3, and the synthesis of isophorone is carried out under the action of alkaline catalyst. The catalyst loading ratio in Cat1 and Cat2 is 4:3. The reaction temperature is 340℃, the reaction pressure is 0.1MPa, and the space velocity is 1h -1 The first reaction mixture product 2 obtains unreacted acetone and part of the dimer mesityl oxide 3, mesitylene 4, isophorone 5 and part of the polymer mixture 6.

[0048] The first reaction mixture 2 enters the separation device 8, and is separated to obtain mesitylene 4 and isophorone 5 with higher purity according to the difference in boiling points. The unreacted acetone and part of the dimerization product mesityl oxide 3 are recycled by reflux, and part of the polymer mixture 6 is subjected to tail liquid treatment.

[0049] The acetone conversion rate is >68%, the mesitylene selectivity is >63%, the isophorone selectivity is >35%, the purity of the final product mesitylene is >99%, and the purity of isophorone is >99%.

[0050] Example 3

[0051] like Figure 1 As shown, a production process for catalytic acetone polycondensation to co-produce mesitylene and isophorone, the process method uses acetone as the starting raw material, the acetone raw material 1 sequentially enters the upper section of the co-production mesitylene and isophorone reactor 7 filled with catalyst Cat1 and the lower section Cat2 to synthesize mesitylene and synthesize isophorone, and finally enters the product separation device 8 to obtain mesitylene and isophorone products with higher purity. The production process of acetone polycondensation to co-produce mesitylene and isophorone is as follows:

[0052] Acetone raw material 1 enters the co-production of mesitylene and isophorone reactor 7. The upper section of Cat1 is filled with alkali metal composite oxide catalyst ZnO / Al2O3, and the isophorone synthesis process is carried out under the action of the alkaline catalyst. The lower section of Cat2 is filled with active metal supported catalyst Ta2O5 / SiO2, and the mesitylene synthesis process is carried out under the action of the acidic catalyst. The catalyst loading ratio in Cat1 and Cat2 is 5:1. The reaction temperature is 320℃, the reaction pressure is 0.5MPa, and the space velocity is 2h -1 The first reaction mixture product 2 obtains unreacted acetone and part of the dimer mesityl oxide 3, mesitylene 4, isophorone 5 and part of the polymer mixture 6.

[0053] The first reaction mixture 2 enters the separation device 8, and is separated to obtain mesitylene 4 and isophorone 5 with higher purity according to the difference in boiling points. The unreacted acetone and part of the dimerization product mesityl oxide 3 are recycled by reflux, and part of the polymer mixture 6 is subjected to tail liquid treatment.

[0054] The acetone conversion rate is >65%, the mesitylene selectivity is >21%, the isophorone selectivity is >63%, the purity of the final product mesitylene is >99%, and the purity of isophorone is >99%.

[0055] Example 4

[0056] like Figure 2As shown, a production process for catalytic acetone polycondensation to produce mesitylene and isophorone, the process method uses acetone as the starting raw material, the acetone raw material 1 sequentially enters the synthetic mesitylene reactor 9, the synthetic isophorone reactor 10 for condensation reaction, and finally enters the separation device 8 to obtain mesitylene and isophorone products with high purity. The production process of acetone polycondensation to produce mesitylene and isophorone is as follows:

[0057] The acetone raw material 1 enters the synthetic mesitylene reactor 9, which is filled with an active metal-supported catalyst Ta2O5 / SiO2. The synthetic mesitylene process is carried out under the action of an acidic catalyst. The reaction temperature is 340°C, the reaction pressure is 0.1 MPa, and the space velocity is 2 h -1 The second reaction mixture product 11 obtains the unreacted acetone and part of the dimer mesityl oxide 3, mesitylene 4 and part of the polymer mixture 6 after the reaction.

[0058] Then, the unreacted acetone and part of the dimer mesityl oxide 3, mesitylene 4 and part of the polymer mixture 6 are introduced into an isophorone synthesis reactor 10, which is filled with an alkali metal composite oxide catalyst ZnO / Al2O3, and the isophorone synthesis process is carried out under the action of the alkaline catalyst. The reaction temperature is 340°C, the reaction pressure is 0.1 MPa, and the space velocity is 2 h -1 The third reaction mixture product 12 obtains unreacted acetone and part of the dimer mesityl oxide 3, mesitylene 4, isophorone 5 and part of the polymer mixture 6.

[0059] The third reaction mixture 12 enters the product separation device 8, and is separated to obtain mesitylene 5 and isophorone 6 with higher purity according to the difference in boiling points. The unreacted acetone and part of the dimerization product mesityl oxide 3 are recycled by reflux, and part of the polymer mixture 6 is subjected to tail liquid treatment.

[0060] The acetone conversion rate is >63%, the mesitylene selectivity is >50%, the isophorone selectivity is >45%, the purity of the final product mesitylene is >99%, and the purity of isophorone is >99%.

[0061] Example 5

[0062] like Figure 2 As shown, a production process for catalytic acetone polycondensation to produce mesitylene and isophorone, the process method uses acetone as the starting raw material, the acetone raw material 1 sequentially enters the synthetic mesitylene reactor 9, the synthetic isophorone reactor 10 for condensation reaction, and finally enters the separation device 8 to obtain mesitylene and isophorone products with high purity. The production process of acetone polycondensation to produce mesitylene and isophorone is as follows:

[0063] The acetone raw material 1 enters the synthetic mesitylene reactor 9, which is filled with an active metal-supported catalyst Ta2O5 / SiO2. The mesitylene synthesis process is carried out under the action of an acidic catalyst. The reaction temperature is 300°C, the reaction pressure is 0.5MPa, and the space velocity is 2h -1 The second reaction mixture product 11 obtains the unreacted acetone and part of the dimer mesityl oxide 3, mesitylene 4 and part of the polymer mixture 6 after the reaction.

[0064] Then, the unreacted acetone and part of the dimer mesityl oxide 3, mesitylene 4 and part of the polymer mixture 6 are introduced into an isophorone synthesis reactor 10, which is filled with an alkali metal composite oxide catalyst ZnO / Al2O3, and the isophorone synthesis process is carried out under the action of the alkaline catalyst. The reaction temperature is 280°C, the reaction pressure is 0.5 MPa, and the space velocity is 2 h -1 The third reaction mixture product 12 obtains unreacted acetone and part of the dimer mesityl oxide 3, mesitylene 4, isophorone 5 and part of the polymer mixture 6.

[0065] The third reaction mixture 12 enters the product separation device 8, and is separated to obtain mesitylene 5 and isophorone 6 with higher purity according to the difference in boiling points. The unreacted acetone and part of the dimerization product mesityl oxide 3 are recycled by reflux, and part of the polymer mixture 6 is subjected to tail liquid treatment.

[0066] The acetone conversion rate is >61%, the mesitylene selectivity is >53%, the isophorone selectivity is >42%, the purity of the final product mesitylene is >99%, and the purity of isophorone is >99%.

[0067] Example 6

[0068] like Figure 2 As shown, a production process for catalytic acetone polycondensation to produce mesitylene and isophorone, the process method uses acetone as the starting raw material, the acetone raw material 1 sequentially enters the synthetic mesitylene reactor 9, the synthetic isophorone reactor 10 for condensation reaction, and finally enters the separation device 8 to obtain mesitylene and isophorone products with high purity. The production process of acetone polycondensation to produce mesitylene and isophorone is as follows:

[0069] The acetone raw material 1 enters the synthetic mesitylene reactor 9, which is filled with an active metal-supported catalyst Ta2O5 / SiO2. The mesitylene synthesis process is carried out under the action of an acidic catalyst. The reaction temperature is 300°C, the reaction pressure is 0.1 MPa, and the space velocity is 1 h -1 The third reaction mixture product 12 obtains unreacted acetone and part of the dimer mesityl oxide 3, mesitylene 4, isophorone 5 and part of the polymer mixture 6.

[0070] Then, the unreacted acetone and part of the dimer mesityl oxide 3, mesitylene 4 and part of the polymer mixture 6 are introduced into an isophorone synthesis reactor 10, which is filled with an alkali metal composite oxide catalyst ZnO / Al2O3, and the isophorone synthesis process is carried out under the action of the alkaline catalyst. The reaction temperature is 280°C, the reaction pressure is 0.1 MPa, and the space velocity is 1 h -1 The third reaction mixture product 12 obtains unreacted acetone and part of the dimer mesityl oxide 3, mesitylene 4, isophorone 5 and part of the polymer mixture 6.

[0071] The third reaction mixture 12 enters the product separation device 8, and is separated to obtain mesitylene 5 and isophorone 6 with higher purity according to the difference in boiling points. The unreacted acetone and part of the dimerization product mesityl oxide 3 are recycled by reflux, and part of the polymer mixture 6 is subjected to tail liquid treatment.

[0072] The acetone conversion rate is >68%, the mesitylene selectivity is >63%, the isophorone selectivity is >31%, the purity of the final product mesitylene is >99%, and the purity of isophorone is >99%.

[0073] The results shown in Examples 1 to 6 above illustrate that the process for the co-production of mesitylene and isophorone by condensation of acetone uses a dual reactor in series, which effectively increases the primary conversion rate of acetone to more than 60%, and the product yields of mesitylene and isophorone reach a high level. At the same time, the recycling rate of acetone is high, which meets the requirements of modern green chemical synthesis and reduces the investment and energy consumption of equipment.

[0074] For those skilled in the art, although the embodiments of the present invention have been shown and described above, it is understandable that the above embodiments are exemplary and cannot be construed as limitations on the present invention. Those skilled in the art can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A process for the co-production of mesitylene and isophorone by directional polycondensation of acetone, characterized in that: Acetone is used as raw material and continuously condensed with an acidic catalyst and a basic catalyst under certain temperature and pressure conditions to synthesize mesitylene and isophorone products.

2. The process for co-producing mesitylene and isophorone by directional polycondensation of acetone according to claim 1, characterized in that: The acidic catalyst and the alkaline catalyst are loaded independently in two reactors.

3. The process for co-producing mesitylene and isophorone by directional polycondensation of acetone according to claim 1, characterized in that: The acidic catalyst and the alkaline catalyst are mixed in a same reactor in a certain ratio, and the mixed loading ratio of the acidic catalyst to the alkaline catalyst is 0:10 to 10:

0.

4. The process for co-producing mesitylene and isophorone by directional polycondensation of acetone according to claim 1, characterized in that: The reaction conditions of acetone condensation are: inert gas environment reaction pressure 0.1~0.5MPa, reaction temperature 280℃~380℃, liquid hourly space velocity 1~10h -1 .

5. A process for the co-production of mesitylene and isophorone by directional polycondensation of acetone according to any one of claims 1 to 4, characterized in that: The acidic catalyst is a catalyst for catalyzing the polycondensation of acetone to synthesize mesitylene, including a metal / transition metal supported catalyst.

6. The process for co-producing mesitylene and isophorone by directional polycondensation of acetone according to claim 5, characterized in that: The oxide carrier in the metal / transition metal supported catalyst is one or more of alumina, amorphous silica-alumina, silicon dioxide, zirconium oxide and titanium oxide; The active metal is selected from one or more of vanadium, niobium, tantalum and molybdenum; Calculated by weight percentage, the content of the metallic component is 5% to 10% in terms of oxide.

7. The process for co-producing mesitylene and isophorone by directional polycondensation of acetone according to claim 5, characterized in that: The acidic catalyst is a catalyst for catalyzing the polycondensation of acetone into mesitylene, including a molecular sieve catalyst, and the molecular sieve catalyst is one or more of USY molecular sieve, SAPO molecular sieve, Beta molecular sieve, ZSM-5 molecular sieve and MFI molecular sieve.

8. The process for co-producing mesitylene and isophorone by directional polycondensation of acetone according to claim 6, characterized in that: The acidic catalyst is Ta2O5 / SiO2.

9. A process for the co-production of mesitylene and isophorone by directional polycondensation of acetone according to any one of claims 1 to 4, characterized in that: The alkaline catalyst is a catalyst for catalyzing the polycondensation of acetone into isophorone, including an alkali metal oxide / composite oxide catalyst or an alkali metal hydroxide / composite oxide catalyst; Alkali metal oxide / oxide catalyst, the oxide in the alkali metal hydroxide / oxide catalyst is selected from one or more of aluminum oxide, zirconium oxide and titanium oxide; The metal in the alkali metal oxide or its hydroxide is one or more of zinc, calcium and magnesium; Calculated by weight percentage, the content of alkali metal, calculated as oxide or hydroxide, is 5% to 10%.

10. The process for co-producing mesitylene and isophorone by directional polycondensation of acetone according to claim 9, characterized in that: The alkaline catalyst is ZnO / Al2O3.

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